An access tunnel is known from the prior art in accordance with PCT/DE2013/000513, which has a plurality of tunnel elements, whereby the access tunnel can be adapted to the required length. It is known in detail from this citation that two tunnel elements are pushed into one another to protect the individual tunnel elements from contamination, and also from weather effects overall. Provision is furthermore made in this respect that a substantially rigid tunnel element as a base element has at least one further tunnel element in the manner of a concertina for extension, with the substantially rigid tunnel element as the base element being able to receive the tunnel element formed in the manner of a concertina in it in the manner of a garage.
Another access tunnel to an aircraft is known from FR 28 86 624 A, which has both a plurality of telescopic tunnel elements and two rigid tunnel elements at the end sides that are intended to serve as guide elements on the moving of the access tunnel. This access tunnel is thus variable in length. Thus the space requirements of the access tunnel on the airport apron are variable.
Yet another access tunnel to an aircraft is known from WO 01/88274 A1, wherein individual tunnel elements are telescopically connected to one another. It is disadvantageous in this respect that if a plurality of such tunnel elements are telescopically connected to one another, the clearance width reduces more and more over the length of the tunnel elements. Therefore the number of the tunnel elements that may be connected in such a manner are absolutely limited. It is also disadvantageous that, due to the guiding of the individual tunnel elements into one another, a substantial force is required to pull the individual elements apart to form the access tunnel. This is because, as already stated, the frameworks of the individual tunnel elements are connected to one another in a guided manner.
All the previously described access tunnels are furthermore disadvantageous as they are difficult to handle during transportation over the airfield, and the small diameter of the rollers of the tunnel elements that form the access tunnel makes it difficult to guide them on the airport apron. Accordingly, there exists a need in the art for an alternative or improved design for an access device to an aircraft.